CVE-2022-30007
📋 TL;DR
GXCMS V1.5 has a file upload vulnerability in the template management page that allows authenticated attackers to upload malicious PHP files. This can lead to remote code execution and complete server compromise. Only GXCMS V1.5 installations with background/admin access are affected.
💻 Affected Systems
- GXCMS
📦 What is this software?
Gxcms by Gxcms Project
⚠️ Risk & Real-World Impact
Worst Case
Complete server takeover with attacker gaining full control over the web server, data exfiltration, and lateral movement to other systems.
Likely Case
Webshell deployment leading to data theft, defacement, or use as a foothold for further attacks.
If Mitigated
Limited impact with proper file upload restrictions and web application firewalls blocking malicious uploads.
🎯 Exploit Status
Exploitation requires authenticated access to the admin panel. The vulnerability is straightforward to exploit once authenticated.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: None available
Restart Required: No
Instructions:
No official patch available. Consider upgrading to a newer version if available or implementing workarounds.
🔧 Temporary Workarounds
Restrict file upload extensions
allConfigure web server to block .php file uploads in template directories
# Apache: Add to .htaccess in template directory
<FilesMatch "\.(php|php5|php7|phtml)$">
Order Allow,Deny
Deny from all
</FilesMatch>
# Nginx: Add to server block
location ~* \.(php|php5|php7|phtml)$ {
deny all;
}
Implement file type validation
allAdd server-side validation to reject PHP file uploads
# Example PHP validation snippet
$allowed_extensions = array('html', 'htm', 'txt', 'css', 'js');
$file_extension = pathinfo($_FILES['file']['name'], PATHINFO_EXTENSION);
if (!in_array(strtolower($file_extension), $allowed_extensions)) {
die('Invalid file type');
}
🧯 If You Can't Patch
- Restrict admin panel access to trusted IP addresses only
- Implement web application firewall with file upload protection rules
🔍 How to Verify
Check if Vulnerable:
Check if you can upload a .php file through the template management interface after authenticating to the admin panel.Check Version:
Check GXCMS version in admin panel or look for version information in source files.Verify Fix Applied:
Attempt to upload a .php file through the template management interface - it should be rejected.📡 Detection & Monitoring
Log Indicators:
- Unusual file uploads to template directories
- .php files appearing in template folders
- Multiple failed upload attempts
Network Indicators:
- POST requests to template upload endpoints with PHP file extensions
- Unusual outbound connections from web server
SIEM Query:
source="web_server_logs" AND (uri="*template*" AND method="POST" AND file_extension="php")